Grand Prismatic Spring

Grand Prismatic Spring is the name of the largest hot spring in the U.S. and the third largest in the world. It is located in western Yellowstone National Park in the U.S. state of Wyoming.

Generally

The basin is about 75 × 91 m and about 49 m deep. It flows per minute on average 2000 liters of 71 ° C hot water from the source.

The colors come from single-cell micro-organisms ( bacteria and archaea ) in the biofilm at the edges of the mineral-rich thermal spring. They move between green and red and depend on the content of chlorophyll and carotenoids of the respective adjusted to the water temperature from microorganisms. In the summer of biofilm tends to orange and red, whereas in the winter prevails rather dark green.

The water in the center of the source is due to the prevailing temperatures free from microorganisms. The deep blue color of the relative small body of water is due to the water depth and high purity water in the source center front.

History

The first records of this source comes from early European explorers and surveyors.

In 1839, a group of American Fur Company trappers crossed the Midway Geyser Basin and wrote a note about a " boiling lake of 300 feet ", which is about 91 m and thus could apply to the Grand Prismatic Spring.

1870 attended the Washburn - Langford - Doane Expedition and the source told additionally from a nearby geyser (now Excelsior Geyser ), the " measured 50 feet " ( about 15 m).